Dental process.



F. A. CARTER.

DENTAL PROCESS.

APPLICATION FILED 111:0. so, 1910.

Patented Aug. 27, 1912.

W136 roe sass nNrT D STATES. PATENT OFFICE.

FRANCIS A. CARTER, OF CHICAGO, ILLINOIES.

DENTAL rRocEss.

Specification 'of Letters Patent.

Application filed December 30, 1910. Serial No. 600,101.

metal plates for supporting artificial teeth.

By my process artificial teeth are interchangeably secured to the castmetal plates in such a manner that, if for any reason one of the teethbecomes broken in use, it may readily be replaced by a similar toothwithout remodeling in any way the metal plate or parts permanentlycarried thereby.

An essential feature of my process is the employment of an intermediatemeans between the tooth and the metal plate such.

that it may be engaged in the casting operation to be securely andpermanently held in proper position upon the plate, while such means atthe same time permits the proper and individual adjustment of the toothduring the process of making the plate, so that the teeth may beproperly occluded. The intermediate means employed is of such a naturethat it will removably support the teeth and may conveniently consist ofindividual backing plates for the several teeth; each backing platebeing provided with projections adapted to be engaged and retained bythe mounting plate during the casting operation, and conformed also toengage the teeth to hold them properly in position, so that they may beremoved subsequently, if necessary, and new teeth applied. Obviously,other means may be employed than backing plates for accomplishing thisresult, as will be seen by reference to the accompanying drawings inwhich- Figure 1 is a perspective view of a model of the patients mouthand a wax pattern of the plate in place thereon, showing some ofthe'teeth mounted upon the pattern, while others of the teeth have beenremoved to show the mounting means. Figs. 2, 3 and 4 show side views ofthe teeth removed from the mounting means shown in Fig. 1. Fig. 5 is atransverse sectional view through the teeth shown in Fig. 1, toillustrate the relation between the teeth, their mounting them. Fig. 6shows in sectional view, along the line 66 in Fig. 5, a portion of themold made by means of the wax pattern shown in Fig. 1. Figs. 7 and 8 areenlarged transverse sectional views of two of the teeth Patented Aug.27, 1912.

means, and the wax pattern supporting shown in Fig. 5, removed fromtheir backing plates to more clearly show the construction employed.Fig. 9 shows in a view similar to Figs. 7 and 8 a modified form ofbacking plate. metal plate and tooth, in which a backing plate of theform shown in Fig. 9 is employed.

Fig. 10 is a sectional view through a 1 Similar numerals refer tosimilar parts throughout. the several views.

In carrying out my process a model 1 is first made, as is customary inthe art, of the mouth of the patient for whom the plate is to be made. Athin sheet of beeswax 2' is applied to the model 1 and warmed and.

with the teeth of the other jaw. Melted beeswax is applied around thebacking plates to build up the pattern 2 and securely hold the backingplates in position.

The backing plates may be of different conformation, as shown at 4 and5, or the;

mounting means \may consist of pins as shown at 6. The construction ofthe backing plate 4 is shown more clearly in Fig. 7, from which it willbe seen that slots 7 are made through such backing plate from its upperedge to receive the heads of the pins 8 extending from the lingualsurface of the.

tooth 9. The backing plate 4 has extending from its lingual surfaceanchors 10, having enlarged heads to be surrounded by the wax formingthe pattern 2, by "means of which the backing plate 4 is securely heldin position.

The backing plate 5 is shown more clearly in Fig. 8 and is provided withtwo slots 11,.

preferably of dove-tailed conformation, extending through the upper edgeof the plate, as'indlcated in.Fig. l, and adapted to receive the headsof the pins 12 extending from the lingual surface of the tooth 13.-

The backing plate 5 has secured to its lingual surface a second plate14,-the edges of which are beveled asindicated, to afi'ord en-. gagementwith the wax of the pattern 2 during the adjusting operation andultimately a to afford engagement with the metal of the mounting plate,so that the backing plate 5 may be securely held in proper positionu'poh such mounting plate. For some forms of teeth it may be desired toemploy pins. as shown at 6 in Fig. 1 to support them instead of backinplates 4 and 5; and such pins are prefera ly provided with headsextending into and surrounded by the pattern 2, the projecting endsbeing adapted to enter suitable openings 15 formed therefor, asindicated in Fig. 5. A tooth 16 adapted to be used with a mounting pin 6is shown in side view in Fig. ,3. I do not wish to secure claims in thiscase as to the mounting or backing plates as they form the subject matter of another application.

After the teeth and their mounting means are properly adjusted upon thepattern 2, it is to be understood that the wax of the pattern surroundsthe anchors formed on the backs oft-he backingeplates or the heads ofthe pins in case they used; but that the wax does not engage the teethin any way. The next step .in forming the metal plates is to remove theteeth without disturbing the mounting means and then the pattern 2 withthe backing plates and mounting pins is placed in the flask 17, as shownin Fig. 6, and surrounded by investing material 18, in fluid condition,the customary sprue opening 19 being formed at the to of the flask. Whenthe material 18 has ardened tho flask is heated sufliciently to causethe wax of the pattern to flow from the sprue opening 19, while thebacking plates and mounting pins are held in roper position by thematerial 18.

terial l8 completely fills all of the openings in the backing plates tobe engaged by the teeth and their supporting pins, and also completelysurrounds the portions of the mounting pins to be surrounded ultimatelyby the teeth; and that the anchor portions of the backing plates and theheads of the mountin pins extend into the mold 20 as indicate Meltedmetal, as aluminum, silver, or gold, is then poured into the moldthrough the sprue opening in the manner usual in the art, and flowsaround the anchors formed on the backing plates and also around theheads of the mounting pins. When the plate thus cast has coo-ledsufiiciently the flask is opened and the material 18 removed carefully,after which the metal corresponding to the sprue opening 19 is removedand the plate 1s trimmed and polished in the usual manner. The result isthe counterpart of the pattern 2 with all of the teeth removed. Cementis then placed in the slots in the backing plates and in the openings 15in the teethto be placed u on the mounting pins, and the teeth are t enplaced in the position upon the cast plate For this condition, as shownm Fig. 6 it will be understood that the ma-' that they originallyoccupied upon the finished pattern, and the plate is complete.

As a result of the process described, it will be observed that theindividual means employed to mount the teeth are securely held in placeupon the. mounting plate with a portionof such mounting means; and thatthe mounting plate thus produced constitutes in connection with theindividual mounting means a permanent rigid structure, affording foreach teeth a support adapted to the particular requirements of suchtooth regardless of the requirements of the other teeth. Inaddition tothe flexibility of adjustment secured by my means for mounting the teethdirectly upon the a cast metal plate, as the teeth are secured to themounting means by cement, they may subsequently be readily removed ifthis becomes necessary through breakage, and other teeth may be readilymounted in their place without in any way changing the mounting plate orthe mounting means.

In Fig. 9 a modified form of backing plate 21 is shown having an anchor22 similar to the anchors 10, shown in Fig. 7, and provided on its frontface with a projecting prong 23, conformed as indicated in Fig. 10 toenter an opening formed in the lingual face of the tooth, such openingextending also longitudinally of the tooth, as a result of which whenthe tooth 24 is secured upon the prong 23 by means of cement the tooth24 is rigidly locked in position, so that there is no danger of it beingpulled from the prong while the teeth are in use.

The mounting or backing plate is claimed in another copendingapplication.

While I have shown the particular means herein described for carryingout my improved process, I do not wish to be understood as limitingmyself to these means, for I may employ any equivalent devices that willsuggest themselves to those skilled in the art without changing theessential steps involved in my invention.

' What I claim is:

1. The dental process consisting in making a model of'the mouth to befitted, making upon such model a wax pattern'of the plate to be cast,supporting teeth upon such pattern by mounting means engaged by thepattern, adjusting the teeth and mounting means to the positionrequired, removing the teeth from the mounting means, surrounding thepattern and mounting means with investing material, heating, thematerial to melt the pattern, pouring melted metal into the mold thusmade, finishing the cast plate, and mounting the teeth upon theirrespective mounting means by means plate to'be cast, supporting teethupon such pattern by mounting means engaged by the pattern, adjustingthe teeth and mounting means to the position required, removing theteeth from the mounting means, surroundmg investing material, heatingthe material to melt the pattern, and introducing melted metal into themold thus made.

3. The dental process consisting in making a pattern of the part to becast carrying mounting means to receive and support artithe pattern andmounting means with ficial teeth, surrounding the pattern and mountingmeans With investing materlal, removing the pattern from the investingmaterial, and introducing melted metal into the mold thus made.

In Witness whereof, I hereunto subscribe my name this 22nd day ofDecember, A. D.,

